Ethylene Glycol → HCID 14601399, compound
Reaction equation
[S:1]1[C:5]([CH:6]=[O:7])=[CH:4][C:3]2[S:8][CH:9]=[CH:10][C:2]1=2.[CH2:11](O)[CH2:12][OH:13].S(C1C=CC(C)=CC=1)([O-])(=O)=O.[NH+]1C=CC=CC=1>C1C=CC=CC=1>[O:7]1[CH2:11][CH2:12][O:13][CH:6]1[C:5]1[S:1][C:2]2[CH:10]=[CH:9][S:8][C:3]=2[CH:4]=1Participants
Reactant 3
Product 1
Reagents, catalysts & solvents 1
Procedure
2,3-Dibromothiophene (1) is converted to 3-Bromothiophene-2-carboxaldehyde (2) through a series of reactions with n-butyl lithium yielding 2-litho-3-bromothiophene, followed by N-formylpiperidine and 3N HCl. This 3-bromothiophene-2-carboxaldehyde (2) is then placed in toluene solution containing ethylene glycol to which is added pyridinium tosylate yielding 3-bromo-2-(2-dioxolanyl)thiophene (3). This 3-bromo-2-(2-dioxolanyl)thiophene (3) is then reacted with n-butyllithium followed by sulfur, then by methyl bromoacetate, to yield methyl 3-[2-(2-dioxolanyl)thiophene-3-yl]-3-thiapropionate (4). This methyl 3-[2-(2-dioxolanyl)thiophene-3-yl]-3-thiapropionate (4) is next dissolved in acetone and p-toluenesulfonic acid monohydrate is added in catalytic amount yielding methyl 3-(2-formylthiophene-3-yl)-3-thiapropionate (5). This methyl 3-(2-formylthiophene-3-yl)3-thiapropionate (5) is then treated in solution with piperidinium acetate yielding methyl thieno[3,2-b]thiophene-2-carboxylate (6). This methyl thieno[3,2-b]thiophene-2-carboxylate (6) is then placed in solution with lithium aluminum hydride yielding 2-hydroxymethylthieno[3,2-b]-thiophene (7). This 2-hydroxymethylthieno[3,2-b]-thiophene (7) is then added to a suspension of pyridinium chlorochromate in methylene chloride and yields thieno[3,2-b]thiophene-2-carboxaldehyde (8). This thieno[3,2-b]thiophene-2-carboxaldehyde (8) is then mixed with ethylene glycol, pyridinium tosylate and benzene yielding 2-(2-dioxolanyl)thieno[3,2-b]thiophene (9). This 2-(2-dioxolanyl)thieno[3,2-b]thiophene (9) is then reacted with n-butyllithium after which SO2 is bubbled onto the surface and N-chlorosuccinimide and NH4OH are added separately at the appropriate time. This series of steps yields 5-(2-dioxolanyl)thieno[3,2-b]thiophene-2-sulfonamide (10). This 5-(2-dioxolanyl)thieno[3,2-b]thiophene-2-sulfonamide (10) may then be reacted with p-toluenesulfonic acid monohydrate in acetone to yield 5-formylthieno[3,2-b]thiophene-2-sulfonamide (11). The 5-formylthieno[3,2-b]thiophene-2-sulfonamide (11) is then reacted with an appropriate amine yielding the intermediate iminium salt (12) which may then be reduced with NaBH4 or NaCNBH3 to give the desired 5-substituted thieno[3,2-b]thiophene-2-sulfonamide.
Sources & evidence
- ORD record
- ord-0e58542f280d456d9f99da6451621d7d
- Source dataset
- uspto-grants-1989_10
- Patent number
- US04876271
Reaction notes
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